Transcript of "Osstmm.3"

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OSSTMM 3 – The Open Source Security Testing Methodology Manual
This manual provides test cases that result
in verified facts. These facts provide
actionable
information
that
can
measurably improve your operational
security. By using the OSSTMM you no
longer have to rely on general best
practices,
anecdotal
evidence,
or
superstitions because you will have
verified information specific to your needs
on which to base your security decisions.
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OSSTMM 3 – The Open Source Security Testing Methodology Manual
Instructions
This is a methodology to test the operational security of physical locations, human interactions, and all
forms of communications such as wireless, wired, analog, and digital. Those who want to jump right into
testing while using it may find the following quick-start information helpful.
Quick Start
To start making an OSSTMM test you will need to track what you test (the targets), how you test them (the
parts of the targets tested and not the tools or techniques used), the types of controls discovered, and
what you did not test (targets and parts of the targets). Then you may conduct the test as you are
accustomed to with the objective of being able to answer the questions in the Security Test Audit Report
(STAR) available at the end of this manual or as its own document. The STAR gives the specific test
information on the state of the scope for the benefits of having a clear statement of the security metrics
and details for comparisons with previous security tests or industry test averages. More details on the
required information for the STAR is available throughout this manual and can be referenced as needed.
As you may see, taking this approach means that very little time is required in addition to a standard test
and the formalization of the report. It has been reported that this methodology actually reduces testing
and reporting time due to the efficiencies introduced into the process. There should be no time or
financial reason to avoid using the OSSTMM and no unreasonable restrictions are made to the tester.
Upgrading from Older Versions
If you are familiar with the OSSTMM 2.x series then you will find that the methodology has completely
changed. The new rav provides a factual attack surface metric that is much more accurate for
measuring the susceptibility to attacks. There are many other changes and enhancements as well but the
primary focus has been to move away from solution-based testing which assumes specific security
solutions will be found in a scope and are required for security (like a firewall). Another change you may
notice is that there is now a single security testing methodology for all channels: Human, Physical, Wireless,
Telecommunications, and Data Networks.
The rav information from 2.x to 3.0 is incompatible. Those with early 3.0 draft rav (prior to RC 12) will require
that the values be re-calculated using this final attack surface calculation which is available as a
spreadsheet calculator at http://www.isecom.org/ravs. Previous OSSTMM security metrics measured risk
with degradation however this version does not. Instead, the focus now is on a metric for the attack
surface (the exposure) of a target or scope. This allows for a factual metric that has no bias or opinion like
risk does. Our intention is to eventually eliminate the use of risk in areas of security which have no set price
value of an asset (like with people, personal privacy, and even fluctuating markets) in favor of trust
metrics which are based completely on facts.
Much of the terminology has changed in this version to provide a professional definition of that which can
actually be created or developed. This is most notable in definitions for security and safety which take
more specific and concrete meanings for operations within.
Since so much has changed from previous versions, as this is a completely re-written methodology, we
recommend you read through it once before using it. Further help is available at http://www.isecom.org.
Courses to help you make thorough and proper security tests, systems, and processes are available
through ISECOM and will help you get the most of the OSSTMM.
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OSSTMM 3 – The Open Source Security Testing Methodology Manual
Version Information
The current version of the Open Source Security Testing Methodology Manual (OSSTMM) is 3.02. This
version of the OSSTMM ends the 2.x series. All OSSTMM versions prior to 3.0 including 3.0 release
candidates (RC versions) are now obsolete.
The original version was published on Monday, December 18, 2000. This current version is published on
Tuesday, December 14, 2010.
About this Project
This project is maintained by the Institute for Security and Open Methodologies (ISECOM), developed in
an open community, and subjected to peer and cross-disciplinary review. This project, like all ISECOM
projects, is free from commercial and political influence. Financing for all ISECOM projects is provided
through partnerships, subscriptions, certifications, licensing, and case-study-based research. ISECOM is a
registered non-profit organization and established in New York, USA and in Catalonia, Spain.
Local Support
Regional ISECOM offices may be available in your area for language and business support. Find the
ISECOM Partner in your area at http://www.isecom.org/tp.
Community Support
Reader evaluation of this document, suggestions for improvements, and results of its application for further
study are required for further development. Contact us at http://www.isecom.org to offer research support,
review, and editing assistance.
Print Edition
The print edition of this manual is available for purchase at the ISECOM website.
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OSSTMM 3 – The Open Source Security Testing Methodology Manual
Restrictions
Any information contained within this document may not be modified or sold without the express consent of
ISECOM. Commercial selling of this document or the information within this document, including the
methodology applied within a tool, software, or checklist may NOT be provided without explicit permission
from ISECOM.
This research document is free to read, free to re-distribute non-commercially, and free to quote or apply in
academic or commercial research, and free to use or apply in the following commercial engagements:
testing, education, consulting, and research.
This manual is licensed to ISECOM under Creative Commons 3.0 Attribution-NonCommercial-NoDerivs and the
Open Methodology License 3.0.
The ISECOM logo is an official Trademark and may not be used or reproduced commercially without consent
from ISECOM. The OSSTMM hummingbird graphic is copyright Marta Barceló Jordan, licensed to ISECOM and
may not be used or reproduced commercially without permission.
As a collaborative, open project, the OSSTMM is not to be distributed by any means for which there is
commercial gain either by itself or as part of a collection. As a standard, there may be only one, official
version of the OSSTMM at any time and that version is not to be altered or forked in any way which will
cause confusion as to the purpose of the original methodology. Therefore, no derivation of the OSSTMM is
allowed.
As a methodology, the OSSTMM is protected under the Open Methodology License 3.0 which applies the
protection as that granted to Trade Secrets. However, where a Trade Secret requires sufficient effort
requirements to retain a secret, the OML requires that the user make sufficient effort to be as transparent as
possible about the application of the methodology. Therefore, use and application of the OSSTMM is
considered as acceptance of the responsibility of the user to meet the requirements in the OML. There are no
commercial restrictions on the use or application of the methodology within the OSSTMM. The OML is available
at the end of this manual and at http://www.isecom.org/oml.
Any and all licensing questions or requests should be directed to ISECOM.
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OSSTMM 3 – The Open Source Security Testing Methodology Manual
Foreword
Security verification used to require a cross-disciplinary specialist who understood security as deeply as
they understood the rules, laws, underlying premise, operation, process, and technology involved.
Sometime later, third party verification came from the popular notion of builder blindness that says those
closest to the target will generally and usually involuntarily miss the most problems. This became the
standard procedure for a while and is still widely regarded as true even though it actually means that an
outsider with less knowledge of the target is supposedly more capable of understanding that target than
the operator. At some point, the pendulum began to swing back the other way. Whether this happened
for either efficiency or economic reasons is unclear, but it has brought about an important shift to provide
the operators with security testing ability. It has led to simplified frameworks, software, checklists, tool kits,
and many other ways to make security testing easy enough that anyone can do it. That’s a good thing.
Unfortunately, there is no complex subject for which the simplification process is not itself complex nor the
end result significantly less than the whole. This means that to make a security testing solution simple
enough for non-experts to execute, the solution requires a complex back-end to collect the data
according to preconceived rules. This assumes that operations always run according to design and
configuration. It also assumes the solution developer has taken into account all the possibilities for where,
what, and how data can be gathered. Furthermore it assumes that the data gathered can be properly
sorted into a uniform format for comparison and rule-based analysis. None of those tasks are simple.
Assuming that can be done, it would still require an exhaustive database of possibilities for the numerous
representations of security and layers of controls to deduce security problems. While minimizing false
positives through correlations based on the rules, laws, underlying premise, operation, process, and
technology involved. This solution could then be able to provide a clear, concise report and metric. This
solution would need to have more than just the framework, software, checklist, or toolkit which it
produces; it would need a methodology.
A security methodology is not a simple thing. It is the back-end of a process or solution which defines what
or who is tested as well as when and where. It must take a complex process and reduce it into elemental
processes and sufficiently explain the components of those processes. Then the methodology must
explain the tests for verifying what those elemental processes are doing while they are doing, moving,
and changing. Finally, the methodology must contain metrics both to assure the methodology has been
carried out correctly and to comprehend or grade the result of applying the methodology. So, m aking a
security testing methodology is no small feat.
With each new version of the OSSTMM we get closer to expressing security more satisfactorily than
previous versions. It’s not that this OSSTMM 3 promotes revolutionary ideas but rather it applies many new
pragmatic concepts which will improve security. We are coming ever closer to truly understanding what
makes us safe and secure.
For a chance of having this enlightenment, I want to thank all the contributors to the OSSTMM, the
ISECOM team, all the ISECOM certified students who care about the right way to do security testing, all
those teaching Hacker Highschool to the next generation, all supporters of the ISECOM projects including
the ISECOM Training Partners, ISECOM Licensed Auditors, and finally my very patient and supportive wife
who understands how important this is to me and to the world we need to improve.
Thank you all for all your help.
Pete Herzog
Director, ISECOM
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OSSTMM 3 – The Open Source Security Testing Methodology Manual
In art, the end result is a thing of beauty,
whereas in science, the means of
reaching the end result is a thing of
beauty. When a security test is an art then
the result is unverifiable and that
undermines the value of a test. One way
to assure a security test has value is to
know the test has been properly
conducted. For that you need to use a
formal methodology. The OSSTMM aims to
be it.
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OSSTMM 3 – The Open Source Security Testing Methodology Manual
Introduction
The Open Source Security Testing Methodology Manual (OSSTMM) provides a methodology for a
thorough security test, herein referred to as an OSSTMM audit. An OSSTMM audit is an accurate
measurement of security at an operational level that is void of assumptions and anecdotal evidence. As
a methodology it is designed to be consistent and repeatable. As an open source project, it allows for
any security tester to contribute ideas for performing more accurate, actionable, and efficient security
tests. Further it allows for the free dissemination of information and intellectual property.
Since its start at the end of 2000, the OSSTMM quickly grew to encompass all security channels with the
applied experience of thousands of reviewers. By 2005, the OSSTMM was no longer considered just a best
practices framework. It had become a methodology to assure security was being done right at the
operational level. As security audits became mainstream, the need for a solid methodology became critical. In
2006, the OSSTMM changed from defining tests based on solutions such as firewall tests and router tests to a
standard for those who needed a reliable security test rather than just a compliance report for a specific
regulation or legislation.
Since environments are significantly more complex than in years past due such things as remote operations,
virtualization, cloud computing, and other new infrastructure types, we can no longer think in simplistic tests
meant only for desktops, servers, or routing equipment. Therefore, with version 3, the OSSTMM encompasses
tests from all channels - Human, Physical, Wireless, Telecommunications, and Data Networks. This also makes it
a perfectly suited for testing cloud computing, virtual infrastructures, messaging middleware, mobile
communication infrastructures, high-security locations, human resources, trusted computing, and any logical
processes which all cover multiple channels and require a different kind of security test. A set of attack surface
metrics, called ravs, provide a powerful and highly flexible tool that can provide a graphical representation of
state, and show changes in state over time. This integrates well with a ’dashboard’ for management and is
beneficial for both internal and external testing, allowing a comparison/combination of the two. Quantitative
risk management can be done from the OSSTMM Audit report findings, providing a much improved result due
to more accurate, error free results however you will find the proposed trust management here to be superior
to risk management. The OSSTMM includes information for project planning, quantifying results, and the rules of
engagement for performing security audits. The methodology can be easily integrated with existing laws and
policies to assure a thorough security audit through all channels.
Legal and industry specific regulations also commonly require a security audit as a component of becoming
compliant. An OSSTMM audit is well suited for most all of these cases. Specific OSSTMM tests can therefore be
connected with particular security standard requirements, making the OSSTMM itself a way to gain
compliance to those requirements. This applies to regulations and policies from physical security like the US
Federal Energy Reserve Commission’s ruling to pure data security efforts such as the latest PCI-DSS and
including cross-channel requirements as found in many NIST recommendations and information security
management specifications like ISO/IEC 27001:2005, ISO/IEC 27002:2005, and ISO/IEC 27005:2008.
It is recommended that you r ead through the OSSTMM once completely before putting it into practice. It
aims to be a straight-forward tool for the implementation and documentation of a security test. Further
assistance for those who need help in understanding and implementing this methodology is available at
the ISECOM website.
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OSSTMM 3 – The Open Source Security Testing Methodology Manual
A Short Note About Language in the OSSTMM
What is an audit? Some of the words used in this document may stray from the
definition you are familiar with. New research often requires updating, enhancing,
or retracting information from the world as we thought we have known it. This is a
normal occurrence and to assist you with the changes, this document does try to
define these words properly in their new context. In this document, an OSSTMM
audit or “audit” is the result of the analysis performed after an OSSTMM test. The
person who performs this function of test and analysis is referred to as the Security
Analyst or just “Analyst”.
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OSSTMM 3 – The Open Source Security Testing Methodology Manual
Purpose
The primary purpose of this manual is to provide a scientific methodology for the accurate
characterization of operational security (OpSec) through examination and correlation of test results in a
consistent and reliable way. This manual is adaptable to almost any audit type, including penetration
tests, ethical hacking, security assessments, vulnerability assessments, red-teaming, blue-teaming, and so
forth. It is written as a security research document and is designed for factual security verification and
presentation of metrics on a professional level.
A secondary purpose is to provide guidelines which, when followed correctly, will allow the analyst to
perform a certified OSSTMM audit. These guidelines exist to assure the following:
1.
2.
3.
4.
5.
6.
The test was conducted thoroughly.
The test included all necessary channels.
The posture for the test complied with the law.
The results are measurable in a quantifiable way.
The results are consistent and repeatable.
The results contain only facts as derived from the tests themselves.
An indirect benefit of this manual is that it can act as a central reference in all security tests regardless of
the size of the organization, technology, or protection.
Document Scope
The scope of this document is to provide specific descriptions for operational security tests over all
operational channels, which include Human, Physical, Wireless, Telecommunications, and Data Networks,
over any vector, and the description of derived metrics. This manual only focuses on OpSec and the use
of the words safety and security are within this context.
Liability
This manual describes certain tests which are designed to elicit a response. Should these tests cause harm
or damage, the Analyst may be liable according to the laws governing the Analyst’s location as well as
the location of the tested systems. ISECOM makes no guarantee as to a harmless outcome of any test.
Any Analyst applying this methodology cannot hold ISECOM liable for problems which arise during
testing. In using this methodology, the Analyst agrees to assume this liability.
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OSSTMM 3 – The Open Source Security Testing Methodology Manual
Certification and Accreditation
To produce an OSSTMM certified test which can receive accreditation for the operational security of the
target, a STAR is required to be signed by the Analyst(s) who performed the test. The STAR must also meet
the reporting requirements in this manual. The STAR can be submitted to ISECOM for review and official
ISECOM certification. A certified test and an accredited report does not need to show that this entire
manual or any specific subsections were followed. It needs only show what was and was not tested to be
applicable for certification. (See Chapter 16, Making the STAR for details and an example of a STAR.)
A certified OSSTMM audit provides the following benefits:





Serves as proof of a factual test
Holds Analyst responsible for the test
Provides a clear result to the client
Provides a more comprehensive overview than an executive summary
Provides understandable metrics
Test review, certification, and accreditation by ISECOM or an accredited third party is subject to further
conditions and operations fees. Contact ISECOM for further information.
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OSSTMM 3 – The Open Source Security Testing Methodology Manual
Certifications for Professionals
Anyone who uses this methodology for security testing and analysis and completes a valid STAR is said to have
performed an OSSTMM audit. However, individual certification is also available through ISECOM for the applied
skills in professional security testing, analysis, methodical process, and professional standards as outlined in the
OSSTMM Rules of Engagement. ISECOM is the authority for a variety of skill and applied knowledge certification
exams based on OSSTMM research. Classes and the official exams are provided by certified training partners in
various regions around the world. The current certification exams available are:
OPST
The OSSTMM Professional Security Tester proves a candidate has the skill and
knowledge to perform accurate & efficient security tests on data networks.
http://www.opst.org
OPSA
The OSSTMM Professional Security Analyst proves a candidate can apply the
principles of security analysis and attack surface metrics accurately & efficiently.
http://www.opsa.org
OPSE
The OSSTMM Professional Security Expert proves a candidate has learned all the
security concepts within the most current, publicly available OSSTMM and the
background to the research.
http://www.opse.org
OWSE
The OSSTMM Wireless Security Expert proves a candidate has the skill and
knowledge to analyze and test the operational security of wireless technologies
across the electromagnetic spectrum accurately & efficiently.
http://www.owse.org
CTA
The Certified Trust Analyst proves a candidate has the skills and knowledge to
efficiently evaluate the trust properties of any person, place, thing, system, or
process and make accurate and efficient trust decisions.
http://www.trustanalyst.org
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OSSTMM 3 – The Open Source Security Testing Methodology Manual
Certifications for Organizations
Certifications for organizations, infrastructure, and products is also available through ISECOM. The following
certifications are available:
Security Test Audit Report
OSSTMM certification is available for organizations or parts of organizations that
validate their security with the STAR from ISECOM. Validation of security tests and
quarterly metrics are subject to the ISECOM validation requirements to assure a
high level of trustworthiness in an organization.
ISECOM Licensed Auditors
ILAs have proven to ISECOM to have the competence and capacity to perform
OSSTMM audits for themselves and for others. This provides for an easy and
efficient way to maintain Security Test Audit Reports and have those reports
certified by ISECOM.
OSSTMM Seal of Approval
OSSTMM evaluation seals are available for products, services, and business
processes. This seal defines an operational state of security, safety, trust, and
privacy. The successfully evaluated products, services, and processes carry their
visible certification seal and rav score. This allows a purchaser to see precisely
the amount and type of change in security that the evaluated solutions present.
It removes the guesswork from procurement and allows one to find and
compare alternative solutions.
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OSSTMM 3 – The Open Source Security Testing Methodology Manual
Related Projects
To properly test the security of anything, you first need to know how that thing operates, what it’s
comprised of, and what is the environment it exists in. This is how the OSSTMM itself had been approached
as a means of understanding the best, most efficient, and most thorough way to test security. Therefore,
we needed to understand security. This research seeking the “security particle” as it turns out has brought
about the application and design of more projects beyond the OSSTMM.
While not all applications of the OSSTMM to areas outside of security testing are worthy of being projects.
However, some do provide a testament to the fact that we are now only limited by our own imaginations.
The OSSTMM has become a tool with which we can take new approaches to many new means of
protection.
Source Code Analysis Risk Evaluation (SCARE)
The SCARE project applies the OSSTMM ravs to source code analysis. The end result is a
SCARE value which is the amount of the source code with unprotected operations.
http://www.isecom.org/scare
Home Security Methodology and Vacation Guide (HSM)
The HSM project applies the OSSTMM ravs, Four Point Process, Trust Metrics, and analysis
process to protecting and fortifying a home. The end result is to create a home that is
safer and more secure without restricting the freedoms of the occupants.
http://www.isecom.org/hsm
Hacker Highschool (HHS)
HHS is a different kind of security awareness program for teens. It uses the OSSTMM
testing and analysis research to provide knowledge and skills through hands-on lessons
and access to an Internet-based test network. However while doing so, it reinforces
resourcefulness and critical thinking skills.
http://www.hackerhighschool.org
The Bad People Project (BPP)
The BPP is a different kind of security and safety awareness program for children and
parents. It uses OSSTMM ravs and Trust Metrics to create better rules for children about
safety and security to be explained through games, stories, and role play. The rules are
easier to remember and free of contradictions and cultural biases. The parents can visit
and contribute to the gallery of children’s drawings which examines what children think
what a bad person looks like. These drawings are the further used to find new ways to
reach children and improve the rules taught to them.
http://www.badpeopleproject.org
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OSSTMM 3 – The Open Source Security Testing Methodology Manual
Security Operations Maturity Architecture (SOMA)
The SOMA project aims to provide the OSSTMM operational processes at the strategic
level. This project applies ravs and Trust Metrics to determining security maturity by how
well protection strategy and tactics work and not just how they should work according
to policy.
http://www.isecom.org/soma
Business Integrity Testing (BIT)
The BIT project extends the OSSTMM operational testing and analysis to business
processes and transactions. This adds new strategic insight to the security of business
conduct by employees and in the development of new business plans.
http://www.isecom.org/bit
Smarter Safer Better
This project provides the safety and security tools and skills people need every day to
combat fraud, lies, and deception. The tools are based on the OSSTMM research which
is focused on avoiding persuasive tricks and manipulation techniques. The project is
unique in how it utilizes support groups for people to discuss issues they have
encountered and work together to analyze the problems.
http://www.smartersaferbetter.org
Mastering Trust
This project is to create seminar materials and workbooks on how to use the OSSTMM
Trust Metrics in every day life to make better decisions. This project addresses why our
gut instincts are broken and how we can fix and improve them. Whether its in business
or private relationships, knowing who you can trust and how much is more than
protecting yourself from being hurt, it´s a competitive edge.
http://www.isecom.org/seminars
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OSSTMM 3 – The Open Source Security Testing Methodology Manual
Chapter 1 – What You Need to Know
This manual is about operational security (OpSec). It is about measuring how well security works. While this
may seem plain and obvious: “Don’t we all do operational security?” it is a distinction which must be
made because most compliance objectives require no more than matching processes and
configurations to a set of best practices. This manual and the testing process it outlines requires that you
make no assumptions that a security solution, product, or process will behave during operational use as it
has been designated to do on paper. More simply, this methodology will tell you if what you have does
what you want it to do and not just what it was told to do.
OpSec is a combination of separation and controls. Under OpSec, for a threat to be effective, it must
interact either directly or indirectly with the asset. To separate the threat from the asset is to avoid a
possible interaction. Therefore it is possible to have total (100%) security if the threat and the asset are
completely separated from each other. Otherwise what you have is safety of the asset which is provided
by the controls you put on the asset or the degree to which you lessen the impact of the threat.
For example, to be secure from lightning, one must move to where lightning can’t reach such as deep in
a mountain. Threats which can’t be separated from the assets must be made safer so that their
interactions and any effects from interactions do little or no harm. In this same example, to be safe from
lightning, one must stay indoors during storms, avoid windows or other openings, and use lightning rods on
the roof. Therefore, under the context of operational security, we call security the separation of an asset
and a threat and safety the control of a threat or its effects.
To have true safety of the assets different types of controls are required. However, controls also may
increase the number of interactions within the scope which means more controls are not necessarily
better. Therefore it is recommended to use different types of operational controls rather than just more
controls. More controls of the same type of operational controls do not provide a defense in depth as
access through one is often access through all of that type. This is why it is so important to be able to
categorize controls by what they do in operations to be certain of the level of protection provided by
them.
To better understand how OpSec can work within an operational environment, it must be reduced to its
elements. These elements allow one to quantify the Attack Surface, which is the lack of specific
separations and functional controls that exist for that Vector, the direction of the interaction. The
reductionist approach resolves to us needing to see security and safety in a new way, one that allows for
them to exist independent of risk and fully capable of creating Perfect Security, the exact balance of
security and controls with operations and limitations. However, to see security in a new way requires new
terminology as well.
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Term
Definition
Attack Surface
The lack of specific separations and functional controls that exist for that
vector.
Attack Vector
Impact and loss reduction controls. The assurance that the physical and
information assets as well as the channels themselves are protected from
various types of invalid interactions as defined by the channel. For
example, insuring the store in the case of fire is a control that does not
prevent the inventory from getting damaged or stolen but will pay out
equivalent value for the loss. Ten controls have been defined. The first five
controls are Class A and control interactions. The five Class B controls are
relevant to controlling procedures. See section 1.2 below for further
information regarding controls.
Controls
Limitations
Operations
Perfect Security
Porosity
A sub-scope of a vector created in order to approach the security testing
of a complex scope in an organized manner. It is based on the divide and
conquer algorithm design paradigm that consists in recursively breaking
down a problem into two or more sub-problems of the same (or related)
type, until these become simple enough to be solved directly.
This is the current state of perceived and known limits for channels,
operations, and controls as verified within the audit. Limitation types are
classified by how they interact with security and safety on an operational
level. Therefore, opinions as to impact, availability in the wild, difficulty to
perform, and complexity are not used to classify them. For example, an old
rusted lock used to secure the gates of the store at closing time has an
imposed security limitation providing a fraction of the protection strength
necessary to delay or withstand an attack. Determining that the lock is old
and weak through visual verification is referred to as an identified limitation.
Determining it is old and weak by breaking it using 100 kg of force when a
successful deterrent requires 1000 kg of force shows a verified limitation.
One of its limitations is then classified based on the consequence of the
operational action, which in this case is Access.
Operations are the lack of security one must have to be interactive, useful,
public, open, or available. For example, limiting how a person buys goods
or services from a store over a particular channel, such as one door for
going in and out, is a method of security within the store’s operations.
The exact balance of security and controls with operations and limitations.
All interactive points, operations, which are categorized as a Visibility,
Access, or Trust.
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Term
Definition
A form of protection where the threat or its effects are controlled. In order
to be safe, the controls must be in place to assure the threat itself or the
effects of the threat are minimized to an acceptable level by the asset
owner or manager. This manual covers safety as “controls” which are the
means to mitigate attacks in an operational or live environment.
Safety
A form of protection where a separation is created between the assets and
the threat. This includes but is not limited to the elimination of either the
asset or the threat. In order to be secure, the asset is removed from the
threat or the threat is removed from the asset. This manual covers security
from an operational perspective, verifying security measures in an
operating or live environment.
Security
The rav is a scale measurement of an attack surface, the amount of
uncontrolled interactions with a target, which is calculated by the
quantitative balance between porosity, limitations, and controls. In this
scale, 100 rav (also sometimes shown as 100% rav) is perfect balance and
anything less is too few controls and therefore a greater attack surface.
More than 100 rav shows more controls than are necessary which itself may
be a problem as controls often add interactions within a scope as well as
complexity and maintenance issues.
Rav
That within the scope that you are attacking, which is comprised of the
asset and any protections the asset may have.
Target
The direction of an interaction.
Vector
Vulnerability
One classification of Limitation where a person or process can access,
deny access to others, or hide itself or assets within the scope. More details
and examples are available in the Limitations table in 4.2.
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1.1 Security
Security is a function of a separation. Either the separation between an asset and any threats exists or it
does not. There are 3 logical and proactive ways to create this separation:
1.
2.
3.
Move the asset to create a physical or logical barrier between it and the threats.
Change the threat to a harmless state.
Destroy the threat.
When analyzing the state of security we can see where there is the possibility for interaction and where
there is not. We know some, all, or even none of these interactions may be required for operations. Like
doors into a building, some of the doors are needed for customers and others for workers. However, each
door is an interactive point which can increase both necessary operations and unwanted ones, like theft.
Since the security tester may not know at this point the business justification for all these interactive points,
we refer to this as the porosity. The porosity reduces the separation between a threat and an access. It is
further categorized as one of 3 elements, visibility, access, or trust which describes its function in
operations which further allows the proper controls to be added during the remediation phase of
improving protection.
So consider that if the separation exists properly from the threats, such as a man inside a mountain
avoiding lightning, then that security is true; it is 100%. For every hole in the mountain, every means for
lightning to cause harm to that man, the porosity increases as an Access. Each point of interaction
reduces the security below 100%, where 100% represents a full separation. Therefore, the increase in
porosity is the decrease in security and each pore is either a Visibility, Access, or Trust.
Term
Visibility
Access
Trust
Definition
Police science places “opportunity” as one of the three elements which
encourage theft, along with “benefit”, and “diminished risk”. Visibility is a
means of calculating opportunity. It is each target’s asset known to exist
within the scope. Unknown assets are only in danger of being discovered as
opposed to being in danger of being targeted.
Since security is the separation of a threat and an asset then the ability to
interact with the asset directly is to access it. Access is calculated by the
number of different places where the interaction can occur. Removing
direct interaction with an asset will halve the number of ways it can be
taken away.
We measure trust as part of OpSec as each relationship that exists where
the target accepts interaction freely from another target within the scope.
While a trust may be a security hole, it is a common replacement for
authentication and a means for evaluating relationships in a rational and
repeatable manner. Therefore, the use of trust metrics is encouraged which
will allow for one to measure how valid a trust is by calculating the amount
of reliability in the trust.
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1.2 Controls
When the threat is all around then it is controls which will provide safety in operations. Controls are a
means to influence the impact of threats and their effects when interaction is required.
Just because you can’t directly control it doesn’t
mean it can’t be controlled. Control the environment
and you control everything in it.
While there are many different names and types of operation controls, there are only 12 main categories
which contain all possible controls. Two of the categories however, Identification, the verification of an
existing identity, and Authorization, the granting of permissions from the rightful authority, cannot stand
alone in an operational environment and instead, in operations, combine and are added to the
Authentication control. This leaves OpSec with ten possible controls an Analyst will need to identify and
understand.
The reason why Identification and Authorization cannot be expressed operationally is because neither
can be transferred. Identity exists as is and while the means of identification, as a process, is an
operational aspect, the actual process is to verify a previously provided identity from another source or
from the latest in a chain of sources. Even under circumstances where a government agency officially
changes the identity of a person, they are still the same person from identifying marks to their DNA and
only their documentation changes. Therefore, a security process can attempt to identify someone by
verifying their identity but nothing in this case is granted or provided. There is no true “granting” of identity
just as there can be no true “theft” of identity. Furthermore, identity is a collection of thoughts, emotions,
experiences, relationships, and intentions, as well as physical shape or marks. You are who you are
because you exist not because someone granted that to you. A perfect duplicate or clone of you is still
not you because from origin your experiences will differ. While this may sound more like philosophy than
security, it is very important that Analysts understand this. Identification processes only verify against a
former identification process. If that process has been corrupted or can be circumvented, then the entire
security foundation that requires proper identification is flawed.
Authorization, like Identification, is another operations control which cannot be transferred. It is the control
to grant permissions. An employee authorized to enter a room may hold the door open for another
person to enter. This does not authorize the new person. Authorization did not get transferred. This new
person is trespassing in a restricted area and the employee who held open the door actually was part of
a limitation in the Authentication process to grant Access.
Another property of Authorization is that it requires identification to work. Without identification,
authorization is a blanket “permit all” without even knowing what all is. However in operations this is itself a
paradox because to authorize all without scrutiny means that there is no authorization. Therefore to not
authorize you do not use authorization.
The Authentication control combines both identification and authorization to map Access. The process is
simply knowing who (or what) it is and what, where, when, and how they can access before they are
granted access. Because authentication is a control for interactivity, it is one of the five Class A controls,
also known as the “Interactive Controls”.
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Interactive Controls
The Class A Interactive Controls make up exactly half of all the operation controls. These controls directly
influence visibility, access, or trust interactions. The Class A categories are Authentication, Indemnification,
Subjugation, Continuity, and Resilience.
1. Authentication is a control through the challenge of credentials based on identification and
authorization.
2. Indemnification is a control through a contract between the asset owner and the interacting
party. This contract may be in the form of a visible warning as a precursor to legal action if posted
rules are not followed, specific, public legislative protection, or with a third-party assurance
provider in case of damages like an insurance company.
3. Resilience is a control over all interactions to maintain the protection of assets in the event of
corruption or failure.
4. Subjugation is a control assuring that interactions occur only according to defined processes. The
asset owner defines how the interaction occurs which removes the freedom of choice but also the
liability of loss from the interacting party.
5. Continuity is a control over all interactions to maintain interactivity with assets in the event of
corruption or failure.
Process Controls
The other half of operation controls are the Class B controls which are used to create defensive processes.
These controls do not directly influence interactions rather they protect the assets once the threat is
present. These are also known as Process Controls and include Non-repudiation, Confidentiality, Privacy,
Integrity, and Alarm.
6. Non-repudiation is a control which prevents the interacting party from denying its role in any
interactivity.
7. Confidentiality is a control for assuring an asset displayed or exchanged between interacting
parties cannot be known outside of those parties.
8. Privacy is a control for assuring the means of how an asset is accessed, displayed, or exchanged
between parties cannot be known outside of those parties.
9. Integrity is a control to assure that interacting parties know when assets and processes have
changed.
10. Alarm is a control to notify that an interaction is occurring or has occurred.
While controls are a positive influence in OpSec, minimizing the attack surface, they can themselves add
to the attack surface if they themselves have limitations. Often times this effect is not noticed and if the
protection mechanisms aren’t tested thoroughly as to how they work under all conditions, this may not
become apparent. Therefore the use of controls must assure that they do not insinuate new attack
vectors into the target. Therefore, sometimes no controls are better than bad controls.
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The Bad Lock Example
Is a bad lock on a door better than no lock at all? An Analyst must use critical security thinking,
a form of logic skills to overcome the innate sense of security we carry to understand why bad
controls can increase the attack surface to greater than no control at all.
Common thought is that adding controls with limitations are better than having none at all. Is it
not better to have a poor lock than to have no lock at all? After all, as conventional wisdom
suggests, a wisdom borne of emotion rather than verification, some “security” is better than
none. This is why the analogy of the lock is such a good example and actually does better to
answer the question then any other because it shows so well how we misunderstand controls
that are so common around us.
Ask anyone who has had to break open a locked door where they kick or hit the door to open
it? That answer differs whether it is a key lock opened from the outside as opposed to a bolt
lock on the inside. There’s a reason for this.
When a lock (which is considered the authentication control) is added to a door, the heavy,
solid door needs to have a space hollowed out and the lock inserted. That creates a limitation,
a weak spot in the door. So does adding a handle. Doors with no handles or internal locks do
not have this limitation. However they require the door to be opened from the inside in another
means. So to open a door with that kind of lock, you kick or hit the door at the handle or lock
mechanism.
If there is a bolt lock, that limitation does not exist because the door remains solid. Those doors
often require a force to open that will sooner break the door than the lock. Doors made to
withstand high pressures have the bolts on the outside and the opening mechanism in the
center of the door as a small hole, like doors on a boat or submarine, to avoid the weaknesses
of hollowing out part of the door.
Now to more directly answer the question: if it is better to have a weak lock than no lock. This
question refers to a door with the minimum, a cheap or simple key lock (authentication) that
can be bypassed by someone who wants to enter. So if we know the authentication is weak,
then we know somebody can get in and even worse, they can do it without damaging the
lock or the door which means we may have no knowledge of the intrusion. If you think, well,
that’s okay because our problem isn’t the real crooks, it’s the opportunists looking for the lowhanging fruit then you’re making a risk decision and that does not affect your attack surface
which is made from what you have and not what you want. Furthermore, by having a lock at
all implies, most of all to the opportunists, that there is something of value inside.
If you add a control, any control, you increase the attack surface of anything. If that new thing
you add brings a new attack vector then you were probably better off without. In some cases,
the new attack vector is smaller than the actual amount of safety the new control gives you.
However, a good control will have no limitations and can shrink the attack surface.
A lock in a door should not be easily subverted or add to the attack surface in a significant
way. Such a lock requires force to open and that adds another control then which the lock
provides, alarm. A broken lock is also a good notification of a break-in.
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1.3 Information Assurance Objectives
To facilitate understanding of operation controls, they can be matched back to the three Information
Assurance Objectives of Confidentiality, Availability, and Integrity. These objectives are used across the
information security industry although due in part to their over-simplification, they are more for the benefit
of managing it rather than creating it or testing it. The mapping is not a perfect 1:1 however it is sufficient
to demonstrate operation controls according to the basic CIA Triad. Because the definitions used for CIA
are very broad the mappings appear to be as such:
Information Assurance Objectives
Operation Controls
Confidentiality
Confidentiality
Privacy
Authentication
Resilience
Integrity
Availability
Integrity
Non-repudiation
Subjugation
Continuity
Indemnification
Alarm
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1.4 Limitations
The inability of protection mechanisms to work are their limitations. Therefore the state of security in regard
to known flaws and restrictions within the operations scope is called Limitation. It is the holes,
vulnerabilities, weaknesses, and problems in keeping that separation between an asset and a threat or in
assuring controls continue working correctly.
Limitations have been classified into five categories and these categories define the type of vulnerability,
mistake, misconfiguration, or deficiency by operation. This is different from how limitations are classified
under most security management frameworks and best practices which is why we use the term Limitation
rather than more common terms to avoid confusion. Those other terms refer to vulnerabilities or
deficiencies because they are categorized by the type of attack or often the threat itself. There is a focus
on the risk from the attack. However, to remove bias from security metrics and provide a more fair
assessment we removed the use of risk. Risk itself is heavily biased and often highly variable depending on
the environment, assets, threats, and many more factors. Therefore, under OpSec, we use the term
Limitations to express the difference of categorizing how OpSec fails rather than by the type of threat.
Since the number and type of threats cannot be known it makes more sense to understand a security or
safety mechanism based on when it will fail. This allows the Analyst to test for the conditions in which it will
no longer sustain the necessary level of protection. Only once we have this knowledge can we begin to
play the what-if game of threats and risks. Then we can also invest in the appropriate type of separation
or controls required and create precise plans for disasters and contingencies.
Although the Limitations are categorized here as 1 through 5 this does not mean they are in a hierarchical
format of severity. Rather they are numbered only to differentiate them both for operational planning and
metrics. This also means it is possible that more than one type of Limitation can be applied to a single
problem. Furthermore, the weight (value) of a particular Limitation is based on the other available and
corresponding controls and interactive areas to the scope, there can be no specific hierarchy since the
value of each is specific to the protective measures in the scope being audited.
Within the OSSTMM the five Limitation classifications are:
1. Vulnerability is the flaw or error that: (a) denies access to assets for authorized people or processes,
(b) allows for privileged access to assets to unauthorized people or processes, or (c) allows
unauthorized people or processes to hide assets or themselves within the scope.
2. Weakness is the flaw or error that disrupts, reduces, abuses, or nullifies specifically the effects of the
five interactivity controls: authentication, indemnification, resilience, subjugation, and continuity.
3. Concern is the flaw or error that disrupts, reduces, abuses, or nullifies the effects of the flow or
execution of the five process controls: non-repudiation, confidentiality, privacy, integrity, and
alarm.
4. Exposure is an unjustifiable action, flaw, or error that provides direct or indirect visibility of targets or
assets within the chosen scope channel.
5. Anomaly is any unidentifiable or unknown element which has not been controlled and cannot be
accounted for in normal operations.
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Limitations Mapping
To better understand how Limitations fit into the OpSec framework, it can be seen mapping back to
security and safety:
Category
OpSec
Operations
Class A Interactive
Controls
Class B Process
Limitations
Visibility
Access
Trust
Authentication
Indemnification
Resilience
Subjugation
Continuity
Non-Repudiation
Confidentiality
Privacy
Integrity
Alarm
Exposure
Vulnerability
Weakness
Concern
Anomalies
This mapping shows how Limitations effect security and how there values are determined.
A vulnerability is the flaw or error that: (a) denies access to assets for authorized people or processes (b)
allows for privileged access to assets to unauthorized people or processes, or (c) allows unauthorized
people or processes to hide assets or themselves within the scope. This means that Vulnerability must be
mapped to all points of interaction or OpSec and because Vulnerability can circumnavigate or nullify the
Controls, these must also be considered in the weighting of Vulnerability.
A weakness is a flaw in Class A Controls however can impact OpSec therefore it is mapped to all OpSec
parameters as well as being mapped to this interactive class of controls.
A concern can only be found in Class B Controls however can impact OpSec therefore it is mapped to all
OpSec parameters as well as being mapped to this process class of controls.
An exposure gives us intelligence about the interaction with a target and thus maps directly to Visibility
and Access. This intelligence can also help an attacker navigate around some or all controls and so
Exposure is also mapped to both Control classes. Finally, Exposure has no value itself unless there is a way
to use this intelligence to exploit the asset or a Control and so Vulnerabilities, Weaknesses and Concerns
also play a role in the weighting of Exposure’s value.
An anomaly is any unidentifiable or unknown element which has not been controlled and cannot be
accounted for in normal operations. The fact that it has not been controlled and cannot be accounted
for signifies a direct link with Trust. This Limitation can also cause anomalies in the way Controls function
and so they are also included in the weighting. Finally, as with an Exposure, an Anomaly alone does not
affect OpSec without the existence of either a Vulnerability, Weakness or Concern which can exploit this
unusual behavior.
Additionally, more than one category can apply to a limitation when the flaw breaks OpSec in more than
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one place. For example, an Authentication control which allows a person to hijack another person’s
credentials has a Weakness and should the credentials allow Access then it also has a Vulnerability.
In another example, an Authentication control uses a common list of names corresponding to e-mail
addresses. Every address which can be found or guessed and used as a log-in is an Exposure while the
control itself has a Weakness for its inability to identify the correct user of the Authentication mechanism of
the log-in. If any of those credentials allow Access then we include this as a Vulnerability as well.
Justification for Limitations
The concept that limitations are only limitations if they have no business justification is false. A limitation is a
limitation if it behaves in one of the limiting factors as described here. A justification for a limitation is a risk
decision that is met with either a control of some kind or merely acceptance of the limitation. Risk
decisions that accept the limitations as they are often come down to: the damage a limitation can
cause does not justify the cost to fix or control the limitation, the limitation must remain according to
legislation, contracts, or policy, or a conclusion that the threat does not exist or is unlikely for this particular
limitation. Since risk justifications are not a part of calculating an attack surface, all limitations discovered
must still be counted within the attack surface regardless if best practice, common practice, or legal
practice denotes it as not a risk. If it is not then the audit will not show a true representation of the
operational security of the scope.
Managing Limitations
Another concept that must be taken into consideration is one of managing flaws and errors in an audit.
The three most straightforward ways to manage limitations is to remove the problem area providing the
interactive point altogether, fix them, or accept them as part of doing business known as the business
justification.
An audit will often uncover more than one problem per target. The Analyst is to report the limitations per
target and not just which are the weak targets. These limitations may be in the protection measures and
controls themselves, thus diminishing OpSec. Each limitation is to be rated as to what occurs when the
problem is invoked, even if that invocation is theoretical or the verification is of limited execution to restrict
actual damages. Theoretical categorization, where no verification could be made, is a slippery slope and
should be limited to cases where verification would reduce the quality of operations. Then, when
categorizing the problems, each limitation should be examined and calculated in specific terms of
operation at its most basic components. However, the Analyst should be sure never to report a “flaw
within a flaw” where the flaws share the same component and same operational effect. An example of
this would be a door broken open with a broken window. The door opening is an Access even if the
broken window is also but both are for the same component, the door way, and same operational effect,
an opening. An example from Data Networks would be a computer system which sends a kernel reply,
such as an ICMP “closed port” T03C03 packet for a particular port. This interaction is not counted for all
such ports since the Access comes from the same component, the kernel, and has the same operational
effect, sending a T03C03 packet per port queried.
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1.5 Actual Security
The role of the Controls is to control the porosity in OpSec. It’s like having ten ways of controlling threats
that come through a hole in a wall. For each hole, a maximum of ten different controls can be applied
which bring security back up towards and sometimes above 100%. Limitations then reduce the
effectiveness of OpSec and Controls. The result of an audit which discovers and shows the Security,
Controls, and Limitations is effectively demonstrating Actual Security.
Actual Security is a term for a snapshot of an attack surface in an operational environment. It is a
logarithmic representation of the Controls, Limitations, and OpSec at a particular moment in time. It is
logarithmic because it represents the reality of size where a larger scope will have a larger attack surface
even if mathematically the Controls will balance the OpSec. Using this as building blocks to better
understand how security works, the visualization that we create from this is the effective balance created
between where an attack can occur, where the Controls are in place to manage an attack, and the
limitations of the protective measures.
Another benefit of mathematical representation of an attack surface as Actual Security is that besides just
showing where protection measures are lacking it can also show the opposite. Since it is possible to have
more controls than one needs this can be mathematically represented as more than 100% rav. Whether a
risk assessment may make this point seem impossible, the mathematical representation is useful for
showing waste. It can be used to prove when money is being overspent on the wrong types of controls or
redundant controls.
1.6 Compliance
Compliance is a different thing than security and exists separate from security. It is possible to be
compliant yet not secure and it is possible to be relatively secure but non-compliant and therefore of low
trustworthiness.
Compliance projects are not the time to redefine operational security requirements as a result of an
OSSTMM test, they may however be the time to specify the use of OSSTMM testing, on a periodic basis, to
fulfill a control requirement drafted as a result of a trust assessment that has scoped the minimum number
of controls required to achieve a compliant (but not necessarily secure) state.
The big problem with compliance is it requires a lot of documentation that has to be versioned and
updated. This documentation can be of business processes, narratives, trust assessments, risk assessments,
signed off design tests, operational audits, attestations, and so on and on. This documentation is
scrutinized by internal and external auditors and has to logically fulfill its existence in the world of a
compliant state.
Most recent compliance efforts have been driven by the short term requirements of imposed regulations
with short term implementation requirements. This has created a lot of resource requirements and cost.
Given time to think about it we try to build compliance and evidence production into a process and
manage this resource requirement and cost.
Compliance is a broad brush approach to the application of best practice from, as far as Information
Technology is concerned, the likes of COBIT and ITIL; an OSSTMM test should provide documentation that
provides an understandable, verifiable level of quality. The use of the OSSTMM, however, is designed to
allow the Analyst to view and understand security and safety. Therefore, with the use of this methodology,
any compliance is, at least, the production of evidence of governance within the business process of
security.
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Chapter 2 – What You Need to Do
Where do you start? Testing is a complicated affair and with anything complicated, you approach it in
small, comprehensible pieces to be sure you don’t make mistakes.
Conventional wisdom says complexity is an enemy of security. However, it is only at odds with human
nature. Anything which is made more complex is not inherently insecure. Consider a computer managing
complex tasks. The problem as we know it is not that the computer will make mistakes, confuse the tasks,
or forget to complete some. As more tasks are added to the computer, it gets slower and slower, taking
more time to complete all the tasks. People, however, do make mistakes, forget tasks, and purposely
abandon tasks which are either not important or required at the moment. So when testing security, what
you need to do is properly manage any complexity. This is done by properly defining the security test.
2.1 Defining a Security Test
These 7 steps will take you to the start of a properly defined security test.
1. Define what you want to protect. These are the assets. The protection mechanisms for these assets
are the Controls you will test to identify Limitations.
2. Identify the area around the assets which includes the protection mechanisms and the processes
or services built around the assets. This is where interaction with assets will take place. This is your
engagement zone.
3. Define everything outside the engagement zone that you need to keep your assets operational.
This may include things you may not be able to directly influence like electricity, food, water, air,
stable ground, information, legislation, regulations and things you may be able to work with like
dryness, warmth, coolness, clarity, contractors, colleagues, branding, partnerships, and so on. Also
count that which keeps the infrastructure operational like processes, protocols, and continued
resources. This is your test scope.
4. Define how your scope interacts within itself and with the outside. Logically compartmentalize the
assets within the scope through the direction of interactions such as inside to outside, outside to
inside, inside to inside, department A to department B, etc. These are your vectors. Each vector
should ideally be a separate test to keep each compartmentalized test duration short before too
much change can occur within the environment.
5. Identify what equipment will be needed for each test. Inside each vector, interactions may occur
on various levels. These levels may be classified in many ways, however here they have been
classified by function as five channels. The channels are Human, Physical, Wireless,
Telecommunications, and Data Networks. Each channel must be separately tested for each
vector.
6. Determine what information you want to learn from the test. Will you be testing interactions with
the assets or also the response from active security measures? The test type must be individually
defined for each test, however there are six common types identified here as Blind, Double Blind,
Gray Box, Double Gray Box, Tandem, and Reversal.
7. Assure the security test you have defined is in compliance to the Rules of Engagement, a guideline
to assure the process for a proper security test without creating misunderstandings,
misconceptions, or false expectations.
The end result will be a measurement of your Attack Surface. The attack surface is the unprotected part
of the Scope from a defined Vector.
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2.2 Scope
The scope is the total possible operating security environment for any interaction with any asset which
may include the physical components of security measures as well. The scope is comprised of three
classes of which there are five channels: Telecommunications and Data Networks security Channels of
the COMSEC class, Physical and Human Security Channels of the PHYSSEC class, and the full spectrum
Wireless Security Channel of the SPECSEC class. Classes are from official designations currently in use in the
security industry, government, and the military. Classes are used to define an area of study, investigation,
or operation. However, Channels are the specific means of interacting with assets. An asset can be
anything that has value to the owner. Assets can be physical property like gold, people, blueprints,
laptops, the typical 900 MHz frequency phone signal, and money; or intellectual property such as
personnel data, a relationship, a brand, business processes, passwords, and something which is said over
the 900 MHz phone signal. Often, the scope extends far beyond the reach of the asset owner as
dependencies are beyond the asset owner’s ability to provide independently. The scope requires that all
threats be considered possible, even if not probable. Although, it must be made clear that a security
analysis must be restricted to that which is within a type of certainty (not to be confused with risk which is
not a certainty but a probability). These restrictions include:
1. Non-events such as a volcano eruption where no volcano exists,
2. Non-impact like moonlight through data center window, or
3. Global-impacting such as a catastrophic meteor impact.
While a thorough security audit requires testing all five channels, realistically, tests are conducted and
categorized by the required expertise of the Analyst and the required equipment for the audit.
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OSSTMM 3 – The Open Source Security Testing Methodology Manual
Channels
Class
Channel
Description
Human
Comprises the human element of communication
where interaction is either physical or psychological.
Physical Security
(PHYSSEC)
Physical
Spectrum Security
(SPECSEC)
Wireless
Telecommunications
Communications
Security (COMSEC)
Data Networks
Physical security testing where the channel is both
physical and non-electronic in nature. Comprises the
tangible element of security where interaction
requires physical effort or an energy transmitter to
manipulate.
Comprises all electronic communications, signals,
and emanations which take place over the known
EM spectrum. This includes ELSEC as electronic
communications, SIGSEC as signals, and EMSEC
which are emanations untethered by cables.
Comprises all telecommunication networks, digital or
analog, where interaction takes place over
established telephone or telephone-like network lines.
Comprises all electronic systems and data networks
where interaction takes place over established cable
and wired network lines.
Data Networks
While the channels and their divisions may be represented in any way, within this manual they are
organized as recognizable means of communication and interaction. This organization is designed to
facilitate the test process while minimizing the inefficient overhead that is often associated with strict
methodologies.
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OSSTMM 3 – The Open Source Security Testing Methodology Manual
2.3 Common Test Types
These six types differ based on the amount of information the tester knows about the targets, what the
target knows about the tester or expects from the test, and the legitimacy of the test. Some tests will test
the tester’s skill more than actually testing the security of a target.
Do note when reporting the audit, there is often a requirement to identify exactly the type of audit
performed. Too often, audits based on different test types are compared to track the delta (deviations)
from an established baseline of the scope. If the precise test type is not available to a third-party reviewer
or regulator, the audit itself should be considered a Blind test, which is one with the least merit towards a
thorough security test.
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OSSTMM 3 – The Open Source Security Testing Methodology Manual
Type
1
2
3
4
5
6
Description
Blind
Double Blind
Gray Box
Double Gray
Box
Tandem
Reversal
The Analyst engages the target with no prior knowledge of its defenses, assets, or
channels. The target is prepared for the audit, knowing in advance all the details of
the audit. A blind audit primarily tests the skills of the Analyst. The breadth and depth
of a blind audit can only be as vast as the Analyst’s applicable knowledge and
efficiency allows. In COMSEC and SPECSEC, this is often referred to as Ethical Hacking
and in the PHYSSEC class, this is generally scripted as War Gaming or Role Playing.
The Analyst engages the target with no prior knowledge of its defenses, assets, or
channels. The target is not notified in advance of the scope of the audit, the
channels tested, or the test vectors. A double blind audit tests the skills of the Analyst
and the preparedness of the target to unknown variables of agitation. The breadth
and depth of any blind audit can only be as vast as the Analyst’s applicable
knowledge and efficiency allows. This is also known as a Black Box test or Penetration
test.
The Analyst engages the target with limited knowledge of its defenses and assets
and full knowledge of channels. The target is prepared for the audit, knowing in
advance all the details of the audit. A gray box audit tests the skills of the Analyst. The
nature of the test is efficiency. The breadth and depth depends upon the quality of
the information provided to the Analyst before the test as well as the Analyst’s
applicable knowledge. This type of test is often referred to as a Vulnerability Test and
is most often initiated by the target as a self-assessment.
The Analyst engages the target with limited knowledge of its defenses and assets
and full knowledge of channels. The target is notified in advance of the scope and
time frame of the audit but not the channels tested or the test vectors. A double
gray box audit tests the skills of the Analyst and the target’s preparedness to
unknown variables of agitation. The breadth and depth depends upon the quality of
the information provided to the Analyst and the target before the test as well as the
Analyst’s applicable knowledge. This is also known as a White Box test.
The Analyst and the target are prepared for the audit, both knowing in advance all
the details of the audit. A tandem audit tests the protection and controls of the
target. However, it cannot test the preparedness of the target to unknown variables
of agitation. The true nature of the test is thoroughness as the Analyst does have full
view of all tests and their responses. The breadth and depth depends upon the
quality of the information provided to the Analyst before the test (transparency) as
well as the Analyst’s applicable knowledge. This is often known as an In-House Audit
or a Crystal Box test and the Analyst is often part of the security process.
The Analyst engages the target with full knowledge of its processes and operational
security, but the target knows nothing of what, how, or when the Analyst will be
testing. The true nature of this test is to audit the preparedness of the target to
unknown variables and vectors of agitation. The breadth and depth depends upon
the quality of the information provided to the Analyst and the Analyst’s applicable
knowledge and creativity. This is also often called a Red Team exercise.
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